Chinese e-commerce giant Alibaba Group Holding said its 'Singles' Day' sale saw more than US$5 billion sales within the first hour of the shopathon on Friday, a third more than in the first hour of last year's spree.

The 24-hour event, which is held every year on Nov 11, offers an insight into China's swing to online shopping, especially via smartphones. The event, launched in 2009, is also a benchmark for Alibaba's annual performance. It was designed to encourage consumers without a partner to treat themselves.

This year Alibaba aims to capture global attention with Hollywood actress Scarlett Johansson, sports celebrity David Beckham, basketball legend Kobe Bryant and pop-rock band One Republic.

The Singles' Day organized by this e-commerce giant shifts more goods than the combined goods of Black Friday and Cyber Monday in the United States.

Sales on Alibaba platforms, which include Tmall and Taobao, are tipped to exceed US$20 billion this year, up from $14 billion last year.

Alibaba said on its official microblog that the sales officially started at midnight and it released all the pre-placed orders in those first few hours which were placed by shoppers ahead of the event. This resulted in first billion dollars of transactions in just 5 minutes.

Alibaba is not the only retailer to mark Nov. 11 with a massive sales drive. JD.com Inc, China's second largest e-commerce player and Alibaba rival, and several other companies also offer discount deals on the day.

The popularity of Singles Day reflects how Chinese consumers are racing to shop online especially through their smartphones. On Friday, Alibaba said 84 percent of sales in the first two hours were via mobile devices.

However, reports say false advertising and messaged statistics have created confusion for customers on Singles' Day rising concern in the cut-throat competition.

The business regulator of China warned mainland online shopping platforms this week against suspect sales tactics.